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Heliyon Jun 2018Alkaline proteases have applications in numerous industries. In this study, we have isolated and screened proteolytic bacteria from poultry wastes mixed soil and...
Alkaline proteases have applications in numerous industries. In this study, we have isolated and screened proteolytic bacteria from poultry wastes mixed soil and identified two bacterial isolates as AKAL7 and AKAL11 based on 16S rDNA sequencing. Maximum level of protease production was achieved after 24 h of fermentation in a basal medium. The optimal temperature, initial pH of the media and agitation for alkaline protease production by these two isolates were 30 °C, pH 9.0 and 120 rpm, respectively. The both bacterial isolates produced maximum level of protease with 3.0% organic municipal solid wastes (OMSW) as the sole source of carbon and nitrogen under previously optimized fermentation conditions. In comparison with the shake flask, protease production increased about 2.5-fold in the bioreactor with reduction in fermentation period. The partial purification of protease resulted in a final 45.67 and 34.86-fold purified protease with a specific activity of 8335.34 and 9918.91 U/mg protein and a typical yield of 9.75 and 9.41% from and , respectively. The optimum temperature and pH of the partially purified protease from the both sources was 40 °C and pH 9.0, respectively. Protease from the both isolates was stable at pH 7.0-12.0 and at temperatures up to 50 °C. The effects of protease inhibitors indicated that the protease from might be serine and cysteine type and from might be cysteine type. Mg, K and Ca stimulated but Zn, Hg, Co and Fe strongly inhibited the protease activity. The partially purified protease from substantially dehaired cow skin and decomposed gelatinous compound from X-ray film. Our study revealed that OMSW can be used as raw material for production of bacterial extracellular protease and alkaline protease from might be potential for industrial and biotechnological applications.
PubMed: 30009270
DOI: 10.1016/j.heliyon.2018.e00646 -
Journal of Applied Microbiology Feb 2018The aim of this study was to analyse arsenic (As) transformation and biosorption by indigenous As-resistant bacteria both in planktonic and biofilm modes of growth.
AIMS
The aim of this study was to analyse arsenic (As) transformation and biosorption by indigenous As-resistant bacteria both in planktonic and biofilm modes of growth.
METHODS AND RESULTS
As-resistant bacteria were isolated from industrial waste water and strain PT2, and identified as Exiguobacterium profundum through 16S rRNA gene sequencing was selected for further study. As transformation and biosorption by E. profundumPT2 was determined by HPLC-ICP-MS analysis. Planktonic cultures reduced 3·73 mmol l As into As from artificial waste water effluent after 48-h incubation. In case of biosorption, planktonic cultures and biofilms exhibited 25·2 and 29·4 mg g biomass biosorption, respectively. As biosorption kinetics followed Freundlich isotherm and pseudo second-order model. Biofilm formation peaked after 3 days of incubation, and in the presence of As stress, biofilm formation was significantly affected in contrast to control (P < 0·05). Homogeneous nature of mature biofilms with an increased demand of nutrients was revealed by minimum roughness and maximum surface to biovolume ratio measured through CLSM analysis.
CONCLUSION
Indigenous As-resistant E. profundumPT2 was found capable of As transformation and biosorption both in the form of planktonic cultures and biofilms.
SIGNIFICANCE AND IMPACT OF THE STUDY
Indigenous biofilm forming E. profundum PT2 revealing As biosorption and biotransformation potential is presented an eco-friendly and cost-effective source for As remediation that can be implemented for waste water treatment.
Topics: Adsorption; Arsenic; Bacillaceae; Biofilms; Biomass; Biotransformation; Industrial Waste; Kinetics; RNA, Ribosomal, 16S; Wastewater; Water Pollutants, Chemical
PubMed: 29130635
DOI: 10.1111/jam.13636 -
International Journal of Molecular... Dec 2023Breast cancer (BC) continues to be one of the major causes of cancer deaths in women. Progress has been made in targeting hormone and growth factor receptor-positive BCs...
Breast cancer (BC) continues to be one of the major causes of cancer deaths in women. Progress has been made in targeting hormone and growth factor receptor-positive BCs with clinical efficacy and success. However, little progress has been made to develop a clinically viable treatment for the triple-negative BC cases (TNBCs). The current study aims to identify potent agents that can target TNBCs. Extracts from microbial sources have been reported to contain pharmacological agents that can selectively inhibit cancer cell growth. We have screened and identified pigmented microbial extracts (PMBs) that can inhibit BC cell proliferation by targeting legumain (LGMN). LGMN is an oncogenic protein expressed not only in malignant cells but also in tumor microenvironment cells, including tumor-associated macrophages. An LGMN inhibition assay was performed, and microbial extracts were evaluated for in vitro anticancer activity in BC cell lines, angiogenesis assay with chick chorioallantoic membrane (CAM), and tumor xenograft models in Swiss albino mice. We have identified that PMB from the (PMB1), inhibits BC growth more potently than PMB2, from the strain. The analysis of PMB1 by GC-MS showed the presence of a variety of fatty acids and fatty-acid derivatives, small molecule phenolics, and aldehydes. PMB1 inhibited the activity of oncogenic legumain in BC cells and induced cell cycle arrest and apoptosis. PMB1 reduced the angiogenesis and inhibited BC cell migration. In mice, intraperitoneal administration of PMB1 retarded the growth of xenografted Ehrlich ascites mammary tumors and mitigated the proliferation of tumor cells in the peritoneal cavity in vivo. In summary, our findings demonstrate the high antitumor potential of PMB1.
Topics: Humans; Female; Animals; Mice; Breast Neoplasms; Bacillus subtilis; Exiguobacterium; Cell Cycle Checkpoints; Triple Negative Breast Neoplasms; Plant Extracts; Cell Proliferation; Cell Line, Tumor; Apoptosis; Tumor Microenvironment
PubMed: 38139241
DOI: 10.3390/ijms242417412 -
Frontiers in Microbiology 2021Halotolerant bacteria produce a wide range of bioactive compounds with important applications in agriculture for abiotic stress amelioration and plant growth promotion....
Halotolerant bacteria produce a wide range of bioactive compounds with important applications in agriculture for abiotic stress amelioration and plant growth promotion. In the present study, 17 biosynthetic gene clusters (BGCs) were identified in PHM11 belonging to saccharides, desmotamide, pseudaminic acid, dipeptide aldehydes, and terpene biosynthetic pathways representing approximately one-sixth of genomes. The terpene biosynthetic pathway was conserved in spp. while the PHM11 genome confirms the presence of the 1-deoxy-d-xylulose 5-phosphate (DXP) pathway for the isopentenyl diphosphate (IPP) synthesis. Further, 2,877 signal peptides (SPs) were identified using the PrediSi server, out of which 592 proteins were prophesied for the secretion having a transmembrane helix (TMH). In addition, antimicrobial peptides (AMPs) were also identified using BAGEL4. The transcriptome analysis of PHM11 under salt stress reveals the differential expression of putative secretion and transporter genes having SPs and TMH. Priming of the rice, wheat and maize seeds with PHM11 under salt stress led to improvement in the root length, root diameters, surface area, number of links and forks, and shoot length. The study shows that the presence of BGCs, SPs, and secretion proteins constituting TMH and AMPs provides superior competitiveness in the environment and make PHM11 a suitable candidate for plant growth promotion under salt stress.
PubMed: 35185816
DOI: 10.3389/fmicb.2021.785458 -
Proteomes Feb 2017Since the publication of one of the first studies using 2D gel electrophoresis by Patrick H. O'Farrell in 1975, several other studies have used that method to evaluate... (Review)
Review
Since the publication of one of the first studies using 2D gel electrophoresis by Patrick H. O'Farrell in 1975, several other studies have used that method to evaluate cellular responses to different physicochemical variations. In environmental microbiology, bacterial adaptation to cold environments is a "hot topic" because of its application in biotechnological processes. As in other fields, gel-based and gel-free proteomic methods have been used to determine the molecular mechanisms of adaptation to cold of several psychrotrophic and psychrophilic bacterial species. In this review, we aim to describe and discuss these main molecular mechanisms of cold adaptation, referencing proteomic studies that have made significant contributions to our current knowledge in the area. Furthermore, we use B7 as a model organism to present the importance of integrating genomic, transcriptomic, and proteomic data. This species has been isolated in Antarctica and previously studied at all three omic levels. The integration of these data permitted more robust conclusions about the mechanisms of bacterial adaptation to cold.
PubMed: 28248259
DOI: 10.3390/proteomes5010009 -
Saudi Journal of Biological Sciences Jul 2017The microbial communities associated with the alimentary tract of honey bees are very important as they help with food digestion, provide essential nutrients, protect...
The microbial communities associated with the alimentary tract of honey bees are very important as they help with food digestion, provide essential nutrients, protect the host from pathogens, detoxify harmful molecules, and increase host immunity. In this study, the structural diversity of the gut microbial communities of native honey bees, from two different geographical regions (Riyadh and Al-Baha) of Saudi Arabia was analyzed by culture-dependent methods and 16S ribosomal RNA (rRNA) gene sequencing. In this study, 100 bacterial isolates were cultivated and phylogenetic analyses grouped them into three phyla: Proteobacteria, Firmicutes, and Actinobacteria. Bacteria in the phylum Proteobacteria were the most dominant (17 species), followed by Firmicutes (13 species) and Actinobacteria (4 species). Some of the identified bacteria ( sp., , , and ) were reported for the first time in the genus , while others identified bacteria belonged to the genera , , , , and . To the best of our knowledge, this is the first study on the gut microbiota of the local honey bees in Saudi Arabia.
PubMed: 28663705
DOI: 10.1016/j.sjbs.2017.01.055 -
Frontiers in Microbiology 2019Cellulose is the most abundant organic polymer mainly produced by plants in nature. It is insoluble and highly resistant to enzymatic hydrolysis. Cellulolytic...
BACKGROUND
Cellulose is the most abundant organic polymer mainly produced by plants in nature. It is insoluble and highly resistant to enzymatic hydrolysis. Cellulolytic microorganisms that are capable of producing a battery of related enzymes play an important role in recycling cellulose-rich plant biomass. Effective cellulose degradation by multiple synergic microorganisms has been observed within a defined microbial consortium in the lab culture. Metagenomic analysis may enable us to understand how microbes cooperate in cellulose degradation in a more complex microbial free-living ecosystem in nature.
RESULTS
Here we investigated a typical cellulose-rich and alkaline niche where constituent microbes survive through inter-genera cooperation in cellulose utilization. The niche has been generated in an ancient paper-making plant, which has served as an isolated habitat for over 7 centuries. Combined amplicon-based sequencing of 16S rRNA genes and metagenomic sequencing, our analyses showed a microbial composition with 6 dominant genera including , and in this cellulose-rich niche; the composition is distinct from other cellulose-rich niches including a modern paper mill, bamboo soil, wild giant panda guts, and termite hindguts. In total, 11,676 genes of 96 glucoside hydrolase (GH) families, as well as 1,744 genes of carbohydrate transporters were identified, and modeling analysis of two representative genes suggested that these glucoside hydrolases likely evolved to adapt to alkaline environments. Further reconstruction of the microbial draft genomes by binning the assembled contigs predicted a mutualistic interaction between the dominant microbes regarding the cellulolytic process in the niche, with and acting as helpers that produce endoglucanases, and , and being beneficiaries that cross-feed on the cellodextrins by oligosaccharide uptake.
CONCLUSION
The analysis of the key genes involved in cellulose degradation and reconstruction of the microbial draft genomes by binning the assembled contigs predicted a mutualistic interaction based on public goods regarding the cellulolytic process in the niche, suggesting that in the studied microbial consortium, free-living bacteria likely survive on each other by acquisition and exchange of metabolites. Knowledge gained from this study will facilitate the design of complex microbial communities with a better performance in industrial bioprocesses.
PubMed: 30984144
DOI: 10.3389/fmicb.2019.00618 -
The ISME Journal Jun 2009The genera Exiguobacterium and Psychrobacter have been frequently detected in and isolated from polar permafrost and ice. These two genera have members that can grow at... (Comparative Study)
Comparative Study
The genera Exiguobacterium and Psychrobacter have been frequently detected in and isolated from polar permafrost and ice. These two genera have members that can grow at temperatures as low as -5 and -10 degrees C, respectively. We used quantitative PCR (Q-PCR) to quantify members of these genera in 54 soil or sediment samples from polar, temperate and tropical environments to determine to what extent they are selected by cold environments. These results were further analyzed by multiple linear regression to identify the most relevant environmental factors corresponding to their distribution. Exiguobacterium was detected in all three climatic zones at similar densities, but was patchier in the temperate and tropical samples. Psychrobacter was present in almost all polar samples, was at highest densities in Antarctica sediment samples, but was in very low densities and infrequently detected in temperate and tropical soils. Clone libraries, specific for the 16S rRNA gene for each genus, were constructed from a sample from each climatic region. The clone libraries were analyzed for alpha and beta diversities, as well as for variation in population structure by using analysis of molecular variance. Results confirm that both genera were found in all three climatic zones; however, Psychrobacter populations seemed to be much more diverse than Exiguobacterium in all three climatic zones. Furthermore, Psychrobacter populations from Antarctica are different from those in Michigan and Puerto Rico, which are similar to each other.
Topics: Antarctic Regions; Climate; Cluster Analysis; Colony Count, Microbial; DNA, Bacterial; DNA, Ribosomal; Gram-Positive Bacteria; Michigan; Molecular Sequence Data; Phylogeny; Psychrobacter; Puerto Rico; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Soil Microbiology
PubMed: 19322243
DOI: 10.1038/ismej.2009.25 -
Scientific Reports Jun 2021Exiguobacterium sp. AO-11 was immobilized on bio-cord at 10 CFU g carrier for the removal of crude oil from marine environments. To prepare a ready-to-use...
Exiguobacterium sp. AO-11 was immobilized on bio-cord at 10 CFU g carrier for the removal of crude oil from marine environments. To prepare a ready-to-use bioremediation product, the shelf life of the immobilized cells was calculated. Approximately 90% of 0.25% (v/v) crude oil removal was achieved within 9 days when the starved state of immobilized cells was used. The oil removal activity of the immobilized cells was maintained in the presence of oil dispersant (89%) and at pH values of 7-9. Meanwhile, pH, oil concentration and salinity affected the oil removal efficacy. The immobilized cells could be reused for at least 5 cycles. The Arrhenius equation describing the relationship between the rate of reaction and temperature was validated as a useful model of the kinetics of retention of activity by an immobilized biocatalyst. It was estimated that the immobilized cells could be stored in a non-vacuum bag containing phosphate buffer (pH 7.0) at 30 °C for 39 days to retain the cells at 10 CFU g carrier and more than 50% degradation activity. These results indicated the potential of using bio-cord-immobilized crude oil-degrading Exiguobacterium sp. AO-11 as a bioremediation product in a marine environment.
Topics: Biodegradation, Environmental; Biofilms; Biotransformation; Cells, Immobilized; Exiguobacterium; Hydrogen-Ion Concentration; Petroleum; Petroleum Pollution; Salinity
PubMed: 34155247
DOI: 10.1038/s41598-021-92122-1 -
Nutrients Oct 2017Curcumin has been proven to have a weight-loss effect in a menopausal rat model induced by ovariectomy. However, the effects of curcumin on gut microfloral communities...
Curcumin has been proven to have a weight-loss effect in a menopausal rat model induced by ovariectomy. However, the effects of curcumin on gut microfloral communities of ovariectomized (OVX) rats remains unclear. Here, we used high-throughput 16S rDNA sequencing to explore the effects of curcumin on microbial diversity in the gut of OVX rats. Female Wistar rats were subjected to either ovariectomy or a sham operation (SHAM group). The OVX rats were treated with vehicle (OVX group) or curcumin (CUR group) by oral gavage. After 12-week treatments, the weights of the bodies and uteri of rats were recorded, the levels of estradiol in the serum were assayed by electrochemiluminescence immunoassay (ECLIA). Then, the fragments encompassing V3-V4 16S rDNA hypervariable regions were PCR amplified from fecal samples, and the PCR products of V3-V4 were sequenced on an Illumina MiSeq for characterization of the gut microbiota. Our results showed that, compared to rats in the SHAM group, rats in the OVX group had more weight gain and lower levels of estradiol in the serum, and curcumin could cause significant weight loss in OVX rats but did not increase the levels of estradiol. Sequencing results revealed the presence of 1120, 1114, and 1119 operational taxonomic units (OTUs) found in the SHAM, OVX, and CUR groups, respectively. The percentage of shared OTUs was 86.1603%. Gut microbiota of rats from the SHAM or CUR group had higher levels of biodiversity and unevenness estimations than those from the OVX group. At the phyla level, compared to rats in SHAM group, rats in the OVX group had a higher ratio of phyla and in the gut; at the genus level, four differential gut microbiota (, , , and ) between SHAM and OVX groups were found, whereas seven differential gut microbiota (, , , , , , and ) between OVX and CUR groups were found. In conclusion, estrogen deficiency induced by ovariectomy caused changes in the distribution and structure of intestinal microflora in rats, and curcumin could partially reverse changes in the diversity of gut microbiota.
Topics: Animals; Bacteria; Curcumin; DNA, Bacterial; Estradiol; Feces; Female; Gastrointestinal Microbiome; Models, Animal; Organ Size; Ovariectomy; RNA, Ribosomal, 16S; Rats; Rats, Wistar; Sequence Analysis, DNA; Uterus; Weight Gain
PubMed: 29048369
DOI: 10.3390/nu9101146